The present invention relates to electrical connectors, and more particularly to electrical connectors used to interconnect electronic subassemblies, for example printed circuit boards, which are required to be mounted adjacent to each other often in a vertically stacked configuration.
Prior art methods are known for interconnecting electronic assemblies, particularly circuit boards. For example, it is well known to hard wire the boards together, or to use edge connectors carried by the boards which engage with complimentary fixed edge connectors carried within a frame in which the boards are mounted.
A concern with conventional board-to-board connectors is the limited space for connection of the boards or assemblies within the electronic device. With conventional connectors utilizing a plurality of terminals laterally arranged at intervals in a housing, one contact leg of each terminal is soldered to the circuit pattern of one printed board and the other leg of the contact is soldered to the circuit pattern on the other printed board. As a result of the narrow intervals between the terminals and vertical distance between the boards, it is extremely difficult to solder each of the terminals without bridging an adjacent terminal with solder. The soldering procedure is a time consuming and difficult task.
One suggested improvement is disclosed in the European patent specification Publication No. 0 463 487 published on Jan. 2, 1992. Therein, an electrical connector is described having a terminal housing with a plurality of terminals laterally arranged and fixed at regular intervals with two leg contacts of each terminal extending from the housing. A connector casing loosely accommodates the terminal housing and permits the terminal housing to slide up and down within the casing. The casing in turn has extensions for fixing it to one printed board and means to permit the printed board to come into contact with the other terminals. This device, however, requires an adequate space between the circuit boards to accommodate the connector casing and terminal housing. The minimum distance or height between adjacent circuit boards is thus unnecessarily limited, particularly in a stacked configuration of circuit boards.
The published PCT Application No. WO 97/02631 discloses an electrical connector for connecting adjacent circuit boards, including stacked circuit boards. The connector includes a generally I-shaped insulating body defining a plurality of adjacent recesses into which identical contact elements are mounted. The contact elements have at least one resilient contact arm that resiliently bends or moves within the body recess.
U.S. Pat. No. 5,041,016 and the European Patent Specification No. 0 346 206 disclose other types of printed circuit board connectors.